VODACOM FIDNING WAYS NOT TO CLOSE MY CELLPHONE CONTRACT EVEN AFTER I PAID THEM

I asked Vodacom for a settlement amount for my cellphone contract, i paid it immediately and i was told the account will be closed and i will get the paid up letter, when i called again i was then being told that i owe money, yet i asked for a settlement which i paid, now i paid the amount they asked for and i am yet to receive my paid up letter. I do not understand how the company works, every time you call in you get a different reference to the same problem and you can never get the same person to help you, no email that they reply to, zero competence and accountability.

I need my letter sent to my email ***.